Abstract: A transfer data block is selected, and a data file including the transfer data block is selected as a transfer data file. All the data blocks of the transfer data file are added to the transfer data block. When all the data files including each transfer data block is selected as a transfer data file, the transfer data block is selected as a deletion data block. When a total data amount of the deletion data block is larger than or equal to a predetermined target deletion data amount and a ratio of a total data amount of the transfer data block to the total data amount of the deletion data block is smaller than or equal to a predetermined value, the data file is transferred from a transfer source node to a transfer destination node. Accordingly, a storage can be used efficiently.

Abstract: A first information processing apparatus transmits a message storing a replica of data stored in the first information processing apparatus. The message has an unspecified destination. A first relay apparatus detects a second information processing apparatus provided in a network to which the first relay apparatus belongs. The first relay apparatus selects, as a transfer destination of the message, the second information processing apparatus or a second relay apparatus upon receiving the message. The first relay apparatus transfers the message to the selected transfer destination. The second information processing apparatus stores the replica therein upon receiving the message.

Abstract: A storage apparatus is provided, including a first storage unit; a load information obtaining unit that obtains load information for each of a plurality of portions defined by dividing the first storage unit; a portion identifying unit that identifies a candidate portion that is to be relocated in the first storage unit based on the load information; a determining unit that determines whether or not data in the candidate portion is allowed to be migrated to a second storage unit, the second storage unit having a performance value higher than a performance value of the first storage unit; an adder that adds the second storage unit, when the determining unit determines that the data in the candidate portion is not allowed to be migrated; and a relocation unit that migrates the data in the candidate portion from the first storage unit to the added second storage unit.

Abstract: A storage device being one of a plurality of storage devices storing data includes a memory and a processor coupled to the memory. The processor executes determining, when having received a new request and a new priority information during a preparation for an execution of another update processing, whether a new priority indicated by the new priority information is higher than a priority of the update processing in the preparation. The process including canceling the update processing in the preparation when having determines at the determining that the new priority is higher than the priority of the update processing in the preparation. The process includes forwarding the new request and the new priority information to another storage device when having determined at the determining that the new priority is higher than the priority of the update processing in the preparation.

Abstract: An electronic circuit includes a plurality of delay elements configured to delay a clock signal by a delay time and to supply the delayed clock signal as a delay signal, the delay time being shorter with a higher power source voltage; a delay time acquisition unit configured to acquire the delay time based on a value of the delay signal; and a voltage controller configured to perform a voltage control process in which the power source voltage is controlled to be high in a case where the acquired delay time is longer than a predetermined desired value and the power source voltage is controlled to be low in a case where the acquired delay time is shorter than the predetermined desired value.

Abstract: A semiconductor device includes: a first signal generation section configured to generate an activation signal having a variable duty ratio; and a first processing section configured to perform intermittent operation, based on the activation signal.

Abstract: An oscillator circuit includes: an arithmetic section configured to correct a first input code value and thereby generate a first code value that is within a first predetermined range, the arithmetic section being configured to correct a second input code value in correspondence with a correction amount of the first input code value and thereby generate a second code value, and the first predetermined range being narrower than a range of the first input code value; and an oscillation section configured to generate an oscillation signal having a frequency that varies at first sensitivity based on the first code value and varies at second sensitivity based on the second code value, the second sensitivity being higher than the first sensitivity.

Abstract: An index generation request reception unit configured to receive an index generation request for stored data from one or more information processing apparatuses, and a determination unit configured to determine whether an index of data is generated or not in accordance with identification information attached to the index generation request are provided, so that writing of an object is efficiently processed.

Abstract: A computer-readable recording medium stores a program that causes a computer to execute a writing control process that includes receiving a writing request to write a first data to a first storage apparatus; determining a second data from among a series of data and based on a writing sequence of the series of data written to the computer and a count of storage areas at a second storage apparatus that sequentially selects from among the storage areas when data is received, a storage area to be over written by the received data, where the second data is written to the first storage apparatus and is identical to data that is stored in the storage area to be selected next at the second storage apparatus; and transmitting copy data of the first data to the second storage apparatus, when the second data has been written to the first storage apparatus.

Abstract: A replication system includes N (>=3) storage devices and N nodes, connected to a host via a 1st network and connected to the N number of storage devices via a 2nd network, each to receive a request for accessing a storage device associated with itself and to have an access with a content in response to the received access request to the storage device, wherein when a node receives a write request of data from the host, each of M nodes (1<M<N) including the node stores the data in the storage device associated with itself, and if first data in a first storage device cannot be read out, the first data stored in another storage device is stored into a second storage device not stored with the first data by transmitting the first data via the second network.

Abstract: An internode put requesting unit detects a time-out with respect to a put request issued to the next node in the order of a multiplexing chain and notifies a put/get executing unit of the time-out. The put/get executing unit sends an error to the previous node in the order of the multiplexing chain or a client and instructs a put-failed-data synchronizing unit to synchronize data failed to be put, and the put-failed-data synchronizing unit performs a synchronization process. A primary makes other put requests wait until completion of the synchronization process. Furthermore, when having received the error, the client issues a get request to the tail end of the multiplexing chain.

Abstract: A storage system having a plurality of storages. The each of the storages include a memory and a processor coupled to the memory. The processor executes a process including transmitting an update request for data which is commonly stored in the plurality of storages according to a predetermined transmission order indicating a path to transfer the update request. The process includes updating data when receiving an update request from another storage. The process includes changing the predetermined transmission order to a transmission order in which one or more storages included in the path are excluded according to the number of times the update request for the data is received.

Abstract: Multiple storage apparatuses are provided, at least part of which are individually incorporated into one of storage groups. Each of multiple control apparatuses is configured to, when assigned one or more of the storage groups each including one or more of the storage apparatuses, control data storage by storing data designating each assigned storage group redundantly in the storage apparatuses of the assigned storage group. An information processing apparatus is configured to, when a storage group with data redundancy being lost is detected, make a change in control apparatus assignment for the storage groups in such a manner that a storage group different from the detected storage group is not assigned to a control apparatus with the detected storage group assigned thereto. Subsequently, the information processing apparatus causes the control apparatus to execute a process of restoring the data redundancy of the detected storage group.

Abstract: An information processing system includes: CPUs; storage devices; switches; dummy storage devices which are with respective storage devices and each of which sends, when receiving an identifying information request, its own identifying information back to a sender of the identifying information request; and dummy CPUs which are associated with respective CPUs and each of which tries to, when receiving an instruction for acquiring identifying information from a dummy storage device, acquire the identifying information of the dummy storage device by transmitting the identifying information request, and sends the identifying information as response information back to a sender device of the acquiring instruction.

Abstract: A storage management apparatus manages a plurality of storage apparatuses in a storage system that disperses and stores data that is made redundant so as to have a predetermined redundancy level. The storage management apparatus includes: a patrol process unit that performs, at a patrol speed, a patrol process of confirming that the plurality of storage apparatuses are being operated normally; a relocating process unit that performs, at a relocating process speed, a relocating process of moving the data between the plurality of storage apparatuses; a recovery process unit that performs, at a recovery process speed, a recovery process of recovering the redundancy level of the data when a fault occurs in the plurality of storage apparatuses; and a processing speed control unit that controls the recovery process speed or a sum of the patrol process speed and the relocating process speed to have a predetermined value.

Abstract: An information processing system includes a plurality of information processing apparatuses connected to each other, and communication is performed between the plurality of information processing apparatuses. Each of the plurality of information processing apparatuses includes a processor.

Abstract: A storage system includes a first storage apparatus that stores a first data group selected, based on an access time of each data among plural data; a second storage apparatus that stores a second data group; and a control apparatus that includes a memory unit that stores a Bloom filter in which a property value is registered, and obtained by extracting a property in identification information of each data among the first data group; a processor that is configured to judge whether the property value obtained by extracting the property in the identification information of given data that is to be accessed among the plural data is registered in the Bloom filter; and transmit an access request for the given data to any one among the first storage apparatus and the second storage apparatus, based on results of judgment of whether the property value is registered.

Abstract: An access method includes: obtaining, by a computer, a result of monitoring a busy rate and a number of access operations per unit time of a storage device, the storage device having a first storage area and a second storage area; calculating a characteristic of correlation between the busy rate and the number of access operations per unit time based on the result; calculating a second number of access operations per unit time based on the characteristic of the correlation such that a sum of a first busy rate corresponding to a first number of access operations per unit time and a second busy rate corresponding to a second number of access operations per unit time becomes equal to or lower than a given busy rate; and controlling a number of operations to access the second storage area per unit time based on the second number of access operations.

Abstract: A data management apparatus sends specific data and key information corresponding to the specific data to another apparatus, when executing a process to change a storage destination of the specific data in which the hash value obtained by applying a predetermined hash function to corresponding key information belongs to a certain range, from the data management apparatus to the other apparatus, and sends the identification information of the other apparatus stored in correspondence with the certain range to a request source of an operation request, when the operation request with respect to data corresponding to key information is received after the process.

Abstract: An information processing apparatus includes a first storage unit and a processor. The first storage unit includes a first storage area. The processor receives a first request to write first data into the first storage area. The processor requests an external apparatus to write the first data into a second storage area in a second storage unit included in the external apparatus. The processor determines whether a first response has been received from the external apparatus. The first response indicates that the first data has been written into the second storage area. The processor writes the first data into the first storage area when the first response has been received. The processor requests, without writing the first data into the first storage area, the external apparatus to write second data stored in the first storage area into the second storage area when the first response has not been received.